The Mutual Correlation of Glucose, Starch, and Beta-Glucan Release During Microwave Heating and Antioxidant Activity of Oat Water Extracts

Starch and beta-glucan are most abundant carbohydrate polymers available in oat products; however, their simultaneous release during extraction depends on morphological and processing conditions of raw material. The study analyzes the mutual correlation between the sample (oat flakes and bran) and treatment types (microwave heating (MW)—1–5 min; conventional heating (CH)—7 min) on water extract properties focusing on beta-glucan, starch, and glucose content as well as the antioxidant activity of water extracts. The strong negative partial coefficient correlation was found between solids-starch (− 0.65) and starch-glucose (− 0.89) content as well as DPPH (− 0.66) antioxidant activity in oat flakes revealing the high release of glucose to the water phase and its prooxidant activity. For the oat bran, positive and very high partial coefficient was found for both glucose (0.98) and beta-glucan (0.98) content in solids while the mutual interaction between them was highly negative (− 0.97), meaning the more beta-glucan, the less glucose in the water phase.